<p>Duplicated string literals make the process of refactoring error-prone, since you must be sure to update all occurrences.</p>
<p>On the other hand, constants can be referenced from many places, but only need to be updated in a single place.</p>
<h2>Noncompliant Code Example</h2>
<p>With the default threshold of 3:</p>
<pre>
public void run() {
  prepare("action1");                              // Noncompliant - "action1" is duplicated 3 times
  execute("action1");
  release("action1");
}

@SuppressWarning("all")                            // Compliant - annotations are excluded
private void method1() { /* ... */ }
@SuppressWarning("all")
private void method2() { /* ... */ }

public String method3(String a) {
  System.out.println("'" + a + "'");               // Compliant - literal "'" has less than 5 characters and is excluded
  return "";                                       // Compliant - literal "" has less than 5 characters and is excluded
}
</pre>
<h2>Compliant Solution</h2>
<pre>
private static final String ACTION_1 = "action1";  // Compliant

public void run() {
  prepare(ACTION_1);                               // Compliant
  execute(ACTION_1);
  release(ACTION_1);
}
</pre>
<h2>Exceptions</h2>
<p>To prevent generating some false-positives, literals having less than 5 characters are excluded.</p>

